Our boiler burns only biomass. Do we still have Scope 1 emissions?

Yes, a little. The CO2 from burning biomass is reported separately as biogenic, outside the Scope 1 total, but methane and nitrous oxide from combustion stay in Scope 1. IPCC defaults for wood are 30 kg methane and 4 kg nitrous oxide per terajoule, roughly 2 tonnes of CO2e per terajoule.

How to calculate

1. Tonnes of biomass times its net calorific value gives terajoules.
2. Times 30 kg CH4 and 4 kg N2O per TJ.
3. Convert with global warming potentials, stating which IPCC report you used.

Report three numbers

• Scope 1 CO2e from methane and nitrous oxide.
• Biogenic CO2, shown separately.
• Any fossil fuel used for start-up, such as diesel or coal.

Evidence on the biomass

Buyers and verifiers ask where it came from. Keep supplier invoices and note whether it is residue, waste or plantation wood.

What Senseible does here

Senseible reads fuel invoices, gas bills and delivery documents into dated, fingerprinted records, so each tonne of CO2 traces back to the document behind it.

• Biomass or waste fuel in a boiler
• Firewood bought by the quintal
• Coal, PNG or biomass boiler

Sources: IPCC 2006 Guidelines, Volume 2 Energy, IPCC AR6 Working Group I, GHG Protocol Corporate Standard

Last reviewed 2026-10-22.